OuterfibreOpen the app
Structural analysis · beams & 2D frames · calc packages

Solve the beam.
Show the working.

Outerfibre is a structural workspace for beams and 2D frames. Model on a drawing board, solve by a named method, and print a calc package another engineer can actually check.

Model / XZ · snap 100 mmSolved ✓
12 kN4 kN/m0.0002.0006.000 m
Shear · V / kN
Moment · M / kN·m
Solves by equilibrium · segmented · matrix stiffnessΣF = 0 checked to 1×10⁻⁹Runs in the browser · nothing to installSI units · kN · m
01 / BEAM

A calculator that draws like you do.

Not a form with a diagram bolted on. You place supports and loads on the beam itself — the model is the input, and your assumptions stay visible.

  • Any support arrangement. Pins, rollers, fixed ends and internal hinges — including propped cantilevers and multi-span beams.
  • Real load cases. Point loads, distributed loads, applied moments — grouped into named cases you can switch without rebuilding the model.
  • The method is named. The solver picks the simplest eligible method — equilibrium, segmented equilibrium or matrix stiffness — and says which one it used.
  • Diagrams to scale. Shear, moment and axial diagrams drawn against the model, with signed extremes labelled at the station they occur.
Propped cantilever · hinge at 3.0 mLC1 · Default
18 kN·m5 kN/mhingefixedroller
02 / THE WORKING

Every number shows its working.

Most software gives you an answer. Outerfibre gives you the derivation: formula, substituted values, result — for every step, on every solve. If a checker can't follow it, it isn't engineering.

Calc package · sheet 01Print / save PDF
01 · Reaction at A — moments about B

R_A = (P·b + w·c·(c/2)) / L

R_A = (12.0×4.0 + 4.0×3.0×1.5) / 6.0

R_A = 11.00 kN ↑
02 · Maximum bending moment

M(x) = R_A·x − P·⟨x−a⟩ − w·⟨x−d⟩²/2

M(2.000) = 11.00 × 2.000

M_max = 22.00 kN·m at x = 2.000 m
03 · Equilibrium check

ΣFy = 11.00 + 13.00 − 12.0 − 4.0×3.0 = 0.000 kN

Equilibrium satisfied · residual < 1×10⁻⁹
OUTERFIBRE
UNTITLED BEAM
SHT 01
CHK ✓
  • Derivations, not data dumps.Reactions, extremes and checks each appear as formula → substitution → result, in the order you'd write them by hand.
  • Equilibrium verified on every solve. ΣF and ΣM residuals are computed and printed — the check is part of the output, not a claim.
  • A package you can issue. Print or save the whole working as a titled, numbered calc package — ready for the project file and the person who signs it.
03 / FRAME

Frames, under the same rules.

The 2D frame workspace handles columns, rafters and portals with the same discipline: model it visibly, solve it by a named method, print the working.

  • Portal frames and plane frames. Members at any angle, pinned or fixed bases, loads on any member.
  • Member-by-member results. Reactions, end forces and axial, shear and moment diagrams for every member — not just a coloured picture.
  • The same calc package. Frame results print with the same working and the same title block as the beam sheets.
Portal frame · pinned basesLC1 · Default
6 kN/mR_AR_B4.0 m9.2 m
04 / On the board

Next: three dimensions.

3D modelling and finite-element analysis are in development. They ship when they meet the same bar as everything above — the working shown, nothing hidden. The 2D tools stay fast in the meantime.

05 / PLANS

Free while we build.

Everything below · today

$0

No card, no trial clock, no locked exports. Paid plans will arrive with team features and 3D — and early users will keep a generous free tier. Until then the deal is simple: use it, break it, tell us.

Open the app FREE
Beam analysissupports, hinges, load cases, diagrams
2D frame analysisportals, member diagrams, reactions
Calc packagesprint-ready working with title block
In your browserlight and dark, nothing to install